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Register a new userAGN feeding and feedback in Fornax A: kinematical analysis of the multi-phase ISM
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Added by
Filippo Marcello Maccagni
Publication date
2021
fields
Physics
and research's language is
English
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We present a multi-wavelength study of the gaseous medium surrounding the nearby active galactic nucleus (AGN) Fornax A. Using MeerKAT, ALMA and MUSE observations we reveal a complex distribution of the atomic (HI), molecular (CO), and ionised gas in its centre and along the radio jets. By studying the multi-scale kinematics of the multi-phase gas, we reveal the presence of concurrent AGN feeding and feedback phenomena. Several clouds and an extended 3 kpc filament -- perpendicular to the radio jets and the inner disk ($rlesssim 4.5$ kpc) -- show highly-turbulent kinematics, which likely induces nonlinear condensation and subsequent Chaotic Cold Accretion (CCA) onto the AGN. In the wake of the radio jets and in an external ($rgtrsim 4.5$ kpc) ring, we identify an entrained massive ($sim$ $10^7$ M$_odot$) multi-phase outflow ($v_{rm OUT}sim 2000$ km s$^{-1}$). The rapid flickering of the nuclear activity of Fornax A ($sim$ 3 Myr) and the gas experiencing turbulent condensation raining onto the AGN provide quantitative evidence that a recurrent, tight feeding and feedback cycle may be self-regulating the activity of Fornax A, in agreement with CCA simulations. To date, this is one of the most in-depth probes of such a mechanism, paving the way to apply these precise diagnostics to a larger sample of nearby AGN hosts and their multi-phase ISM.
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